The present invention relates to plaster type interior textured coating removing compositions. More particularly, it relates to a composition containing one or more alkoxy ether solvents and a low molecular weight alcohol with a blend of surfactants for use in removing painted, textured, plaster type interior coatings from a substrate surface or for removing asbestos lagging. Interior textured coating removing compositions which are effective and safe to use generally and on overhead surfaces have been sought for some time. Previously, the methods for removing such coatings have been sanding off, steaming off or chipping off. When sanding down a whole wall or ceiling, much dust is generated, the whole house is affected. Much time and effort is expended. A huge cleaning up operation is then needed. If it was necessary to hire a sander, this would add significantly to the cost of the exercise. When interior textured coatings are removed by steaming, very often the underlying plaster is damaged. This means that in addition to the cost of hiring the steamer, it is necessary to pay to have the wall replastered prior to further redecoration. Much time and effort is expended by this method. If the chosen method is to manually chip away at the interior textured coating, this is cheaper than hiring a steamer or a sander, but is very slow and laborious. Depending on the care being exercised, some damage to the underlying plaster may be caused. In some cases, older type interior textured coatings contain asbestos fibres. Such fibres are well known to be extremely hazardous to health and if coatings containing asbestos fibres in the United Kingdom are to be removed by paid tradespersons this work has to be undertaken by a licensed contractor. United Kingdom law requires that power tools are not used in the removal of asbestos-containing coatings since such use increases the risk of fragmentation of the hazardous fibres which would produce a multiplied risk of fibre inhalation. For this reason, interior textured coatings containing asbestos have to be manually chipped away to minimize the creation of hazardous fibre-containing dust and to facilitate safe disposal of the material.
The interior textured coating removing composition of the present invention provides a safe, easy to use solution to a common problem. In particular, it softens and hydrates plaster type interior textured coating residues without being corrosive, harmful or irritant to living tissue and within a timescale which would be acceptable to any user, whether trade or homeowner. Also, the underlying plaster will not be damaged. Hence the use of this interior textured coating remover will be quicker, safer and more convenient than any of the other methods which are currently in use. The composition of the present invention can be injected into asbestos fibre-containing coatings (asbestos lagging) to bring about rehydration of the lagging and facilitating wet removal of the fibre-containing material so suppressing the creation of hazardous asbestos-containing dust.
The present invention provides a plaster type interior textured coating remover composition comprising an aqueous mixture, i.e. a solution, of
(A) at least one alkoxy ether solvent;
(B) an alcohol containing from 1 to 6 carbon atoms;
(C) at least one nitrogen-containing compound selected from
(i) compounds having the general formula I 
xe2x80x83wherein R1 is H or group of the formula 
xe2x80x83where R3 is a straight or branched chain 6-22 C alkyl or alkenyl group; R2 is H, or methyl or ethyl; w is 1 or 2; and Q1 is xe2x80x94COOM1 or xe2x80x94SO3M1, in which M1 is an alkali metal cation or an optionally substituted ammonium group;
(ii) compounds having the general formula II 
xe2x80x83wherein R4 is H or xe2x80x94(CH2CH2O)zxe2x80x94H; R5 is a straight or branched chain 6-22 C alkyl or alkenyl group; m is 0 or 1; and each of x, y, and z is an integer wherein the total number of (CH2CH2O) groups is in the range of from 2 to 50;
(iii) an imidazoline compound of the formula III 
xe2x80x83wherein R is a straight or branched chain 7 to 18 C alkyl group and x is a number from 2 to 10;
(iv) a compound of the formula IV 
xe2x80x83in which R is a straight or branched chain 7-18 C alkyl group; R1 is xe2x80x94CH2CH2OH or xe2x80x94(CH2)xe2x80x94xCOONa, where x is 1 or 2, R2 is (CH2)YCOONa, where y is 1 or 2; and R3 is H or xe2x80x94CH2CH2OH; and
(v) an alkyl betaine of the formula V
Rxe2x80x94N+(CH3)2CH2COOxe2x88x92xe2x80x83xe2x80x83(V)
xe2x80x83wherein R is a straight or branched chain 7 to 18 C alkyl group;
(D) a compound having the general formula VI
RZ(QO)nHxe2x80x83xe2x80x83(VI)
xe2x80x83wherein R is a straight or branched chain 6-22 C alkyl or alkenyl or an alkylphenyl group; Z is O or NH; Q is xe2x80x94(CH2)2xe2x80x94 or xe2x80x94(CH2)3xe2x80x94 or a combination thereof; n is such that the Hydrophilic Lipophilic Balance (HLB) of the molecule will be 7.3 to 15.0.
It has been found that the incorporation of a compound having the formula (I) to (V), with a compound of the formula (VI) in association with one or more alkoxy ether solvents and a low molecular weight alcohol improves penetration of the water through emulsion type paint, including vinyl silk, and into the body of the plaster type interior textured coating residues leading to fast and thorough removal of these residues. Preferably, a compound having the formula I will be incorporated and also, preferably a compound having the formula II. After application of a preparation according to this invention, the softened, hydrated plaster type interior textured coating can easily be removed by hand, using a scraper.
The one or more alkoxy ether solvents will typically be present in the composition of the invention in an amount of up to 90%, preferably from 6 to 25%, by weight based on the weight of the composition. The alkoxy ether solvent will usually comprise the main plaster type interior textured coating removing solvent in the composition. It is possible, however, that part of the alkoxy ether solvent content is replaced by one or more other cleaning or coupling solvents. Typical of the alkoxy ether solvents that can be used in the present invention are 1-18C alkyl (preferably 1 to 6C alkyl) monoethers of (poly)ethylene glycol, (poly) propylene glycol and (poly) butylene glycol. For reasons of health and safety, the preferred alkoxy ether solvent will be a propylene glycol ether, such as the methyl monoether of dipropylene glycol.
The composition of the invention also comprises a straight or branched chain alcohol containing from 1 to 6 carbon atoms. Preferably, the alcohol is a monohydric alcohol of the formula ROH, wherein R is a 1-5C alkyl group.
Isopropanol, methanol or ethanol are especially preferred examples of the alcohol used in association with the alkoxy ether solvent. Ethanol will be more preferred than methanol in view of its reduced toxicity. The alcohol will usually be used in an amount of up to 90% by weight, preferably from 0.1 to 25% by weight, based on the weight of the composition.
Softening and hydration of the emulsion or vinyl silk painted surface of the plaster type interior textured coating residue is accomplished by the alkoxy ether solvent with the low molecular weight alcohol in combination with a compound of formula (I) to (V) and a compound of formula (VI). Improved penetration of the alkoxy ether through the thickness of the plaster type interior textured coating residues can be achieved by the incorporation into the composition of a compound having a formula (I) or(II) together with a compound having the formula (VI) above.
In the composition of the invention at least one nitrogen-containing surfactant compound of the formula (I) to (V) will be used.
The compounds of the formula I are as follows: 
wherein R1 is H or a group of the formula 
where R3 is a straight or branched chain 6-22 C alkyl or alkenyl group; R2 is H, or methyl or ethyl; w is 1 or 2; and Q1 is xe2x80x94COOM1 or xe2x80x94SO3M1, in which M1 is an alkali metal cation or an optionally substituted ammonium group;
In the general formula I above the group R1 may be H or an aliphatic acyl group of the formula 
An example of a compound wherein R1 is H is sodium sarcosine, i.e., the sodium salt of N-methylglycine. Preferably, however, the compound of formula I will be an alkali metal or ammonium salt of the reaction product of a 6 to 22 C alkanoic or alkenoic acid with an amino carboxylic acid or amino sulphonic acid. Examples of such 6 to 22 C acids include the fatty acids lauric acid, myristic acid, palmitic acid, stearic acid and oleic acid. In formula I, R2 is H, methyl or ethyl. R2 preferably, however, is a methyl group. The group Q1 is a carboxylate or sulphonate in salt form where the cation is provided by an alkali metal, such as lithium, sodium or potassium or by an ammonium ion or a substituted ammonium ion, xe2x80x94NRxe2x80x2Rxe2x80x3Rxe2x80x2xe2x80x3, where each of Rxe2x80x2,Rxe2x80x3 and Rxe2x80x2xe2x80x3 is independently selected from H, 1-6C alkyl or 2-6C hydroxyalkyl, provided that at least one of Rxe2x80x2,Rxe2x80x3 and Rxe2x80x2xe2x80x3 is not H, for example monoisopropylammonium ion, monoethanolammonium ion, diethanolammonium ion or triethanolammonium ion. Preferred examples of compounds having the formula I include sodium N-lauroylsarcosinate, sodium N-oleoylsarcosinate and sodium N-lauroyltaurinate. The compound having the formula I above is typically present in the composition in an amount from 0 to 25% by weight, preferably 0.1 to 15.0% by weight, based on the weight of the composition.
The compounds of the formula II are as follows: 
wherein R4 is H or xe2x80x94(CH2CH2O)zxe2x80x94H; R5 is a straight or branched chain 6-22 C alkyl or alkenyl group; m is 0 or 1; and each of x, y, and z is an integer wherein the total number of (CH2CH2O) groups is in the range of from 2 to 50.
The compounds of the general formula II are ethoxylated amines. Their surfactant behaviour ranges from cationic, where the degree of ethoxylation is low, to nonionic where the degree of ethoxylation is high. A detailed description of such compounds can be found in xe2x80x9cSurfactants UK 1979xe2x80x9d by Dr Gordon Hollis, pp 129-131. Preferably, the compounds of the general formula II contain a group R5 which is a straight chain 10-18C alkyl or 10-18C alkenyl group (a fatty alkyl or alkenyl group) and have a value for m of O and contain a total number of ethoxy ((CH2CH2O) groups in the range of from 4 to 10, especially about 5. An example of such a compound is ethoxylated oleylamine. The ethoxylated amine will, in general, be used in the composition of the invention in an amount of not greater than 25% by weight.
Examples of such compounds are as follows, wherein R5 is the aliphatic group derived from the indicated fatty amine:
The compounds of the formula III are imidazoline type surfactants. 
wherein R is a straight or branched chain 7 to 18 C alkyl group and x is 2 to 10. Preferably R is an n-heptyl group and x is 2.
The composition of the present invention may include as the, or one of the, nitrogen-containing surfactant part of the composition a compound of the formula IV 
in which R is a straight or branched chain 7-18 C alkyl group; R1 is a group selected from xe2x80x94CH2CH2OH and "Parenopenst"CH2"Parenclosest"xCOONa, where x is 1 or 2, R2 is a group "Parenopenst"CH2"Parenclosest"yCOONa, where y is 1 or 2; and R3 is H or xe2x80x94CH2CH2OH. Preferably the alkyl group R will be a straight chain group to improve the biodegradable properties of the compound. Examples of compounds of the formula IV include sodium cocoamphoacetate (IV, R is coco alkyl (i.e., 12-14 C alkyl), R1 is CH2CH2OH, R2 isxe2x80x94CH2COONa and R3 is xe2x80x94CH2CH2OH), disodium cocoamphodiacetate (IV, R is coco alkyl, R1 and R2 are both xe2x80x94CH2COONa and R3 is xe2x80x94CH2CH2OH), disodium cocoamphodipropionate (IV, R is coco alkyl, R1 and R2 are both xe2x80x94CH2CH2COONa and R3 is CH2CH2OH) and sodium capryloamphopropionate (IV, R is a capryl group, R1 is xe2x80x94CH2CH2OH, R2 is xe2x80x94CH2CH2COONa and R3 is H). Preferably, the compound of formula IV is sodium capryloamphopropionate.
The nitrogen-containing surfactant used in the composition of the invention may be a betaine of the formula (V)
RN+(CH3)2CH2COOxe2x88x92xe2x80x83xe2x80x83(V)
wherein R is a straight or branched chain 7-18 C alkyl group, although a straight chain alkyl group is preferred since these have greater biodegradability than branched chain groups. Preferably the R group is a 12-14 C straight chain alkyl group.
In addition to at least one of the nitrogen-containing compounds above the composition will contain at least one compound of the formula VI
RZ(QO)nHxe2x80x83xe2x80x83(VI)
wherein R is a straight or branched chain 6-22 C alkyl or alkenyl or an alkylphenyl group; Z is O or NH; Q is xe2x80x94(CH2)2xe2x80x94 or xe2x80x94(CH2)3xe2x80x94 or a combination thereof; n is such that the Hydrophilic Lipophilic Balance (HLB) of the molecule will be 7.3 to 15.0.
For reasons of biodegradability, the preferred form of Q will be xe2x80x94(CH2)2xe2x80x94. Compounds of the general formula V are sometimes described as nonionic surfactants. These are usually represented as
R7Z(CH2CH2O)nH
wherein Z is as defined above and R7, the hydrophobe, may be nonylphenyl, a fatty alkyl or alkenyl group and n is the average number of moles of ethylene oxide per mole of R7. By varying the xe2x80x9cnxe2x80x9d number and the nature of R7 a wide variety of surfactant and physical properties, such as the Hydrophilic and Lipophilic Balance (HLB) may be obtained. For example:
N.B. for reasons of biodegradability, the preferred form of R7 will be a straight 6-22 C alkyl or alkenyl chain.
Compounds of the general formula VI are alkoxylates. A detailed description of such compounds can be found in xe2x80x9cSurfactants UK 1979xe2x80x9d by Dr Gordon Hollis, pp 100-135 and p 245. R may be a straight or branched chain 6-22 C alkyl or 6-22 C alkenyl or an alkylphenyl group wherein the alkyl group is a straight or branched chain 6-22 C alkyl. An example wherein R is an alkylphenyl group is 
wherein R6 is a straight or branched chain 6-22 C alkyl group and Q is xe2x80x94(CH2)2xe2x80x94 or xe2x80x94(CH2)3xe2x80x94. An example wherein R is derived from a 12-15 C synthetic alcohol and the HLB of the molecule is 7.8 is
R(OCH2CH2)3OH
Preferably, the compounds of the general formula VI contain a group R which is a straight chain 10-20 C alkyl or alkenyl group (a fatty alkyl or alkenyl group) and have a value for n in the range of 3 to 15, especially about 7. An example of such a compound is ethoxylated cetyl/oleyl alcohol (16-18C). The ethoxylated alcohol will, in general, be used in the composition of the invention in an amount of not greater than 25% by weight.
We have found that improved penetration of pained plaster type interior textured coating residues can be achieved by using a composition which contains a blend of surfactants comprising a compound of the general formula I and a compound of the general formula VI. Instead of, or in addition to, the compound of formula I a compound of formula II may be used. This leads to easier, faster and more effective removal than has hitherto been available. Furthermore, the plaster type interior textured coating removing composition of the invention, after application to a coated substrate, gives rise to water-displaceable residues making it possible to clean the treated surface by washing with water after the greatest bulk of softened plaster type interior textured coating has been removed by a scraper. The water-displaceability of treated plaster type interior textured coating resides remaining after using the composition of the invention on a coated substrate can be improved by using a composition which contains at least one compound of the general formula II together with the compound of the general formula VI.
Other substances may also be incorporated into the plaster type interior textured coating removing composition of the invention. The plaster type interior textured coating removing composition may further contain one or more of waxes, corrosion inhibitors, thickeners, preservatives and additional solvents. The incorporation of a wax, e.g., paraffin wax or vegetable wax, has the effect of retarding evaporation from a layer of plaster type interior textured coating remover by forming a very fine skin over the applied layer. Typically, such a wax will be solid at ambient temperatures, i.e., will have a melting point of at least about 25C, and will be incorporated into the composition at a concentration of from 0.2 to 3.5% by weight based on the weight of the composition. One or more thickeners may also be used in the composition to improve its viscosity in order to facilitate the application of the composition to a coated substrate surface and to cause it to remain on a surface (e.g., vertical or overhead) to which it is applied. Such thickeners and the concentrations used, are known in the art. Other substances may also be incorporated into the plaster type interior textured coating remover composition of the invention. For instance, the action of the thickener may be improved by incorporating into the composition compounds having the general formula (VII)
R8COOHxe2x80x83xe2x80x83VII
wherein R8 is a straight or branched chain 6-22 C alkyl or alkenyl group; and/or a lithium, zinc, calcium, magnesium, aluminium, potassium, sodium, monoethanolammonium, diethanolammonium or triethanolammonium salt thereof. Typically, compounds of the general formula (VII) above will be incorporated into the composition at a concentration of from 0 to 7%, preferably 0.3 to 3% by weight based on the weight of the composition.
It has been found that the composition according to the present invention has use as an asbestos lagging rehydration agent to facilitate the removal, while suppressing dust creation, of asbestos fibre-containing coatings. In such uses the composition will not contain a thickener and may, advantageously, be diluted in water, for example 1 part of composition per 10 parts water to aid the wetting of the asbestos fibre-containing coating.
Furthermore, if it is intended to store or market the plaster type interior textured coating remover compositions of the invention in metal containers, the incorporation of one or more corrosion inhibitors in the composition may be preferred. Such inhibitors, which are known in the art, include as examples sodium metaborate and sodium nitrite.
Additionally, if it is intended to store or display or market the plaster type interior textured coating remover compositions of the invention over a prolonged period, the incorporation of one or more preservatives in the composition may be preferred. Such preservatives, which are known in the art, include as examples alkyl dimethyl benzyl ammonium hydrochloride, polyhexamethylene biguanide hydrochloride, chloromethylisothiazolinone and methylisothiazolinone.
A preferred plaster type interior textured coating remover composition according to the invention may be prepared by the following procedure.
Firstly, water is added to a mixing vessel and the temperature of the water is maintained at a value in the range of from 15xc2x0 C. to 30xc2x0 C. While stirring, the alkoxy ether is added slowly. The surfactant compound of formula I is added slowly and allowed to disperse into the contents of the vessel. Maintaining stirring, the surfactant compound of formula (VI) is added slowly and allowed to disperse into the contents of the vessel. Maintaining stirring, the chosen alcohol is added to the mixture and allowed to disperse into the contents of the vessel. In the event that a thickened plaster type interior textured coating remover composition is required, a thickener (.e.g. a modified cellulose type thickener) is preferably added to the contents of the vessel under constant stirring before the addition of the alcohol.